1. Field of the Invention
This invention relates generally to electromagnetic switching apparatus, and in particular to an improved housing for such an apparatus including means for axially movably securing a damping compression spring therein.
2. Description of the Prior Art
Damping compression springs having enlarged end turns, i.e., an end turn having a diameter greater than the other turns of the spring, for securing the spring in the housing of an electromagnetic switching apparatus are generally known in the art. In one known compression spring of the type described above, the end turn has a diameter which is only slightly greater than the other turns of the spring so that the latter can be inserted beyond the outlined dimension of the spring into a blind hole having a diameter chosen so that the enlarged end turn engages the interior surface of the blind hole and the spring is retained therewithin by the spring force of the enlarged end turn. A typical arrangement of this type is a back-pressure spring which is retained in the blind hole of a contact bridge carrier. The disadvantage of such an arrangement, however, is that free movement of the spring along its axis does not exist.